A nut, flat on top and bottom having 6 flat sides. For items which have internal tapered or straight (parallel) pipe threads, specific electrical conduit size designation, and which when installed, provide a method of tightening to lock the connection, see locknut, electrical conduit. See also locknut, tube fitting. For items having a thickness (or height) exceeding two times the width across the flats, use post, electrical-mechanical equipment. (when height or thickness and/or width across the flats is designated as a tolerance dimension, the maximum dimension will be used to determine compliance.)
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NATO Maintenance and Supply Agency Classification: Nuts of iron or steel
NSN 6105-00-911-2783
NSN 5960-00-775-9056
NSN 5895-01-070-0900
NSN 5895-00-158-4343
NSN 5945-00-644-7525
NSN 6110-00-960-7341
NSN 5960-01-609-6565
NSN 5965-00-642-9879
NSN 6240-01-562-8541
NSN 5998-00-134-8408
NSN 6240-00-052-8001
NSN 5925-01-650-7666